1. Field of the Invention
The present invention relates to an article having interlocking edges and its use in preparing a covering product useful for covering flat surfaces as well as rounded surfaces, particularly useful in preparing a laminate flooring product that is easy to install, easy to repair, essentially glueless in installation and essentially waterproof in use due to the profile and composition of its interlocking edges.
2. Discussion of the Background:
In recent years the use of laminate products in the flooring industry as a replacement or substitute for traditional wood plank flooring has grown tremendously due to the durability and ease of care of the laminate products. However, the laminate flooring products currently available often have several disadvantages.
Many conventional laminate floor products have edges that are machined to fit one into the other. However, the conventional method for preparing such edges provides an interference fit (shown in FIG. 1). In the interference fit type of edge, any glue that is placed in the cutout portion of the edge must be forced out upon insertion of the corresponding edge on an adjacent piece of laminate. Due to the tight fit, however, the fitting together of the laminate pieces often requires pressure and clamps to hold the pieces together. Additionally when the pieces are joined, and the glue is forced out of the cutout edge, there is no way to control the direction in which the glue will exit. It can exit either in an upwards direction towards the visible surface of the flooring or in a downwards direction to the surface adjacent the subflooring. Either of these options can be detrimental to both the appearance and function of the resulting floor.
In U.S. Pat. No. 5,618,602, an improved laminate floor was provided in which the rib and cutout edges of the laminate floor sections are machined in such a manner as to provide an escape path for glue from the cutout edge up to the visible floor surface while maintaining sufficient glue on the edge surface to bond the adjacent sections together.
However, since essentially no glue is allowed to exit from the bottom of the laminate flooring, the resulting floor can encounter problems due to entry of water into the seam formed by the edges from below. Since the substrate for the laminate flooring described therein is fiberboard based (wood based), the entry of water can cause swelling, ultimately resulting in buckling or other distortions in the floor.
Additionally, most laminate flooring requires the use of glue applied at the interface of each flooring section, and for direct gluedown applications glue is placed on the bottom surface of the flooring section to adhere it to the underfloor. Once the glue sets, the resulting floor can be extremely difficult to repair or replace. Additionally, due to expansion and/or contraction within individual sections of laminate flooring, the resulting floor can undergo various stresses causing distortions, buckling, etc., thus marring the appearance of the floor.
A new type of surface covering edge design, particularly in the laminate flooring arena, is needed to overcome these disadvantages.